There are more than 100 million pieces of human-made debris whizzing around the planet. How do we clean it up to keep Earth orbit safe for our satellites and spacecraft?

There are more than 100 million pieces of human-made debris whizzing around the planet. How do we clean it up to keep Earth orbit safe for our satellites and spacecraft?

1 of 7

The Problem

NASA estimates that there are more than 100 million pieces of human-produced space debris in orbit. Only 21,000 or so of those objects are big enough to be tracked by space surveillance sensors. Circling around at speeds upwards of five miles per second, even tiny pieces of space junk can pack a wallop, endangering current and future space missions. Here are a few solutions that have been proposed to clean up the mess in orbit.

Advertisement - Continue Reading Below

2 of 7

JAXA

Use a Giant Net

JAXA, the Japanese space agency, is experimenting with giant magnetic nets developed in consultation with a fishing net manufacturer. JAXA hopes to put the first space nets into service by 2019. The European Space Agency is working on its own version, set for a 2021 launch. Space nets are becoming a fashionable idea for catching more than just space junk: NASA's Innovative Advanced Concepts program funded a study for a net called the WRANGLER that would capture asteroids and large space objects.

Advertisement - Continue Reading Below

3 of 7

EFPL / Swiss Space Center

Build a Giant Space Claw

The Clean Space One is a test satellite built by the Swiss Space Center and the École Polytechnique Fédérale de Lausanne to de-orbit dead satellites by locating, capturing, and throwing debris into the atmosphere, where it will burn up in the intense pressure and friction of reentry. It's set for a 2018 launch into low Earth orbit from an unmanned space plane. Its first two targets will be small,Cubesat-like satellites owned by the agency.

Advertisement - Continue Reading Below

4 of 7

Lockheed-Martin

Tow It

You can net it, you can grab it, but you can also tow it. The ideaof using a space tug to grab old satellites has been around since the beginning of the space race—Lockheed Martin has been batting around tug concepts since at least 1958. It recently introduced the CRS-2, a planned space tug that, along with its intended goal of ISS resupplies, could refurbish satellites, de-orbit nonfunctioning spacecraft, and haul broken satellites to a space station or craft for repair or safe cargo return, to Earth or otherwise.

Advertisement - Continue Reading Below

5 of 7

NASA

Kill It With (Laser) Fire

One of the more (seemingly) crazy proposals to tackle the space junk problem involvesfiring lasers from the ground at objects we want to bring down. Lasers could reduce the expensive need to send new technology up into orbit for cleanup. Instead, firing a laser pulse at a piece of space junk could perturb its orbit enough to drag it back to Earth. However, shooting stuff down from the ground could make for some scary accusations of aggression, depending on who takes out whose trash.

Advertisement - Continue Reading Below

Advertisement - Continue Reading Below

6 of 7

NASA JPL

Grab On and Hold Tight

The American space program takes its best cues from the animal
kingdom. Take, for instance, NASA JPL's Gecko Grippers, tested here on a "Vomit Comet" microgravity test airplane. The grippers are designed to grab onto an orbiting object using microscopic "hairs" that enable a firm grip, just like a gecko's sticky toes. The direction of the hairs determines its "stickiness," and they make it easy to ungrip as well.

Advertisement - Continue Reading Below

7 of 7

ABC-TV

Reduce, Reuse, Recycle

In the above still, Andy Griffith stars in the pilot of a television show called "Salvage," in which a scrappy salesman builds a lunar rocket out of salvaged parts in order to grab artifacts from an Apollo landing site worth millions of dollars. The show may have had a ridiculous conceit, but DARPA has a less ridiculous idea: use a robotic handyman to salvage old satellites, in orbit, for usable parts to create entirely new ones. It could also upgrade satellites still in space, as well as return other parts to the ground.

A Part of Hearst Digital Media
Popular Mechanics participates in various affiliate marketing programs, which means we may get paid commissions on editorially chosen products purchased through our links to retailer sites.